摘要
以2,4-二羟基苯乙酮为原料,经C-异戊烯基化和酚羟基保护制得中间体2-羟基-4-甲氧甲氧基-3,5-二异戊烯基苯乙酮(4)。以对羟基苯甲醛为原料,经C-异戊烯基化和催化环化制得中间体2,2-二甲基-5-甲酰基-2H-1-苯并吡喃(7);4和7经羟醛缩合反应得2'-羟基-3',5'-二异戊烯基-4'-甲氧甲氧基-4,5-(2,2-二甲基-苯并吡喃)-查尔酮(8);8经分子内的迈克尔加成反应得6,8-二异戊烯基-7-甲氧甲氧基-4',5'(2,2-二甲基-苯并吡喃)-二氢黄酮(9);在对甲苯磺酸的催化下,9脱去保护基,首次完成了天然异戊烯基黄烷酮(±)-Lespeflorins A3的全合成。其中8和9为新化合物,其结构经1H NMR,IR和EI-MS表征。
2-Hydroxy-4-[(methoxy) methoxy]-3,5-di-(3-methylbut-2-enyl) acetophenone (4) was obtained by C-prenylation and protection of phenolic hydroxyl group from 2,4-dihydroxyacetophenon.2,2-Dimethyl-5-formyl-2H-1-benzopyran(7) was obtained by C-prenylation and catalytic cyclization from 4-hydroxybenzaldehyde.2'-Hydroxy-3',5'-di-(3-methylbut-2-enyl)-4'-[(methoxy) methoxy]-4,5-(2,2-dimethylbenzopyran) chalcone (8) was prepared by aldol condensation reaction of 4 with 7.6,8-Di-(3-methylbut-2-enyl)-7-[(methoxy) methoxy]-4',5' (2,2-dimethylbenzopyran-flavanone (9)was prepared by intramolecular Michael addition reaction of 8.The total synthesis of natural (±)-Lespeflorins A3 was firstly achieved by deprotection of 9 using p-toluene sulfonic acid as the catalyst.8 and 9 were novel compounds and the structures were characterized by 1H NMR,IR and EI-MS.
出处
《合成化学》
CAS
CSCD
北大核心
2014年第4期492-495,共4页
Chinese Journal of Synthetic Chemistry
基金
国家自然科学基金资助项目(21162021)
教育部"新世纪优秀人才支持计划"资助项目(NCET-09-0860)
宁夏自然科学基金资助项目(NZ1006)